Investigation of Springback Behavior and Process Control for Stamping of Ring-Shaped Workpiece

doi:10.1007/s12204-017-1851-3

Abstract

Abstract: Abstract: Due to the elastic deformation of metal stamping, springback is a serious problem to cause shape deviation and thus reduce precision. The springback behavior of ring-shaped workpiece is investigated in this paper and an auxiliary boss device is proposed to control the springback deformation. A finite element model is developed. The characteristic parameters including boss height, boss angle and boss gap are discussed systematically. It can be concluded that the gap has a positive linear correlation with springback percentage, and the boss angle has an optimal interval of 30°—60° to reduce springback. When the boss height increases, the springback decreases, but the effect weakens when the boss height is larger than 1.0 mm. Then, a response surface analysis is conducted with Design Expert 8.0.5 software and an optimal parameter process window (i.e., boss height from 2.1 to 3.0 mm, boss angle from 53°to 60°and the gap from 0 to 1.2 mm) is obtained. Finally, a set of molds are fabricated and the stamping experiments are conducted. The springback behavior is well controlled. The springback percentage can be decreased from 33% to 6% by using the auxiliary boss device of ring-shaped workpiece.

Key words: metal sheet| ring-shaped workpiece| springback| boss device| finite element model

摘要： Abstract: Due to the elastic deformation of metal stamping, springback is a serious problem to cause shape deviation and thus reduce precision. The springback behavior of ring-shaped workpiece is investigated in this paper and an auxiliary boss device is proposed to control the springback deformation. A finite element model is developed. The characteristic parameters including boss height, boss angle and boss gap are discussed systematically. It can be concluded that the gap has a positive linear correlation with springback percentage, and the boss angle has an optimal interval of 30°—60° to reduce springback. When the boss height increases, the springback decreases, but the effect weakens when the boss height is larger than 1.0 mm. Then, a response surface analysis is conducted with Design Expert 8.0.5 software and an optimal parameter process window (i.e., boss height from 2.1 to 3.0 mm, boss angle from 53°to 60°and the gap from 0 to 1.2 mm) is obtained. Finally, a set of molds are fabricated and the stamping experiments are conducted. The springback behavior is well controlled. The springback percentage can be decreased from 33% to 6% by using the auxiliary boss device of ring-shaped workpiece.

关键词: metal sheet| ring-shaped workpiece| springback| boss device| finite element model

CLC Number:

TG 306

HE Junyi (何俊艺), WANG He (王贺), PENG Linfa (彭林法),YI Peiyun* (易培云), LAI Xinmin (来新民), LIN Zhongqin (林忠钦). Investigation of Springback Behavior and Process Control for Stamping of Ring-Shaped Workpiece[J]. Journal of shanghai Jiaotong University (Science), 2017, 22(4): 385-394.

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